Adjustable jaw wrench

ABSTRACT

A movable member carrying a movable jaw toward and away from a fixed jaw is reciprocated by means of a worm in the well-known manner. A drive mechanism for the worm includes a shaft with a helical groove rotatably mounted in the handle, and a thumb actuated button mounted for reciprocating movement and including a boss extending into the helical groove for rotating the shaft. The helical shaft drives the worm through mating gears.

0 Wmted States Patent [151 3,640, 1 59 Halls et al. 1 Feb. 8, 1972 1ADJUSTABLE J AW WRENCH 2,753,748 7/1956 Schlote ..s1/172 x 3,541,899ll/l970 Tanner..... ....81/l72 X [721 Invemmsg gg zg ffig Alfred R3,125,911 3/1964 Schlote ..s1/172 x 7 1 I [73] Assignee: Space Tool,lnc., Pasadena, Tex. Examiner-1311165 L- Jones, Attorney-Cecil L. Wood22 Flled: Aug. 26, 1970 a 21 Appl. No.2 67,054 a [57] ABSTRACT- 4 Amovable member carrying a movable jaw toward and away 52 us. Cl "81/165,74/457 81/172 a fixed jaw is 'ecipmcated by means the 51 Int. Cl..'.....B2sb 13/16 n' A drive meChanism the [58 Field ofSearch ..s1/172165- 74/457 434 dudes shaft with a helical Mammy mwmed handle, and athumb actuated button mounted for reciprocating movement and including aboss extending into the helical [56] References Cited groove forrotating the shaft. The helical shaft drives the worm UNITED STATESPATENTS through mating s Tredwell ..74/457 10 Claims, 7 Drawing FiguresPATENTED FEB 8 I972 DZVETJTORS Kenneth E Hulls Alfred H. BrickleyATTORNEY ADJUSTABLE JAW WRENCH BACKGROUNDAND SUMMARY OF-THE INVENTIONThis invention relates to adjustable jaw wrenches for use in tighteningand loosening bolts andnuts; and more particularly to an adjustingmechanism for themovable jaw ofawrench.

The invention is particularly concerned with improved means foradjusting the movable jaw of a crescent type wrench. In conventionalwrenches of this type, the movable jaw member is reciprocated by meansof a worm, thethreads of which are knurled and extend from one or bothsides of the wrench to be rotated by the thumb of the user. Suchwrenchesare generally satisfactory; however, the rotation of the-worm in thismanner is slow and considerable'time is requiredtoeffect substantialopening and closing movement of the jaws. A wrenching operation may beparticularly time consumingin situations where the wrench-is used inclose quarters with limited room for swinging the handle, thusnecessitating frequent disengagement and reengagement of the wrench froma hex nut, for example.

While a number of designs have been proposed for an adjustable jawwrench having operating mechanisms actuated'by a simple sliding motionof the thumb as opposed'to the rotation of the knurled worm, suchproposals have not-resultediin commercially'successful devices possiblydue to the costs involved in producing such wrenches.

A principal object of this invention is to provide an adjustable jawwrench having an improved mechanism for. quickly and easily effectingrapid adjustment of the spacing between the wrench jaws.

Another object of this invention is to provide an adjustable jaw wrenchhaving an improved jaw adjusting mechanism which is readily operated bythe user while holding the wrench in only one hand.

Another object of this invention is to provide an adjustable jaw wrenchhaving an improved jaw adjusting mechanism which results in much greaterefficiency of use of the wrench.

A further object of this invention is to provide an adjustable jawwrench having an improved jaw adjusting mechanism, which may beeconomically manufactured and assembled.

Still another object of this invention is to provide an adjustable jawwrench having an improved jaw actuating mechanism operated by a thumbactuated member slidably mounted on the wrench handle.

These objects are accomplished in an adjustable jaw wrench including anelongated handle and enlarged head, with the head including a projectingfixed jaw. A movable member slidable on the head, at an angle relativeto the handle,-carries a projecting movable jaw and is reciprocated bymeans of a worm in the usual manner. A shaftrotatably supported in ahandle is provided with a helical groove, and is rotated through a thumbactuated button slidably mounted in the handle and including a bossextending into the groove. The worm is driven through the helical shaftby means of a castellated gear and mating pinion.

The novel features and the advantages of the invention, as well asadditional objects thereof, will be understood more fully from thefollowing description when read in connection with the accompanyingdrawing.

DRAWING FIG. 1 is a view of one side of a wrench according to theinvention;

FIG. 2 is a view of the wrench of FIG. 1 from thesameside, partially insection and with the cover plate removed to show interior construction;

FIG. 3 is a transverse sectional view taken along the line 3- 3 of FIG.2 illustrating the rear bushing for the driving shaft;

FIG. 4 is a transverse sectional viewtaken along the line 4 4 of FIG. 2illustrating the driving shaft actuating button;

FIG. 5 is a sectional view taken through the wrench head along the line5-5 of FIG. 2, illustrating the movable jaw mounting and the worm drive;

LII

FIG. 6'is a. perspective view. of the castellated gear which is fixed tothe drivingshaft; and

FIG. 7 isa view, primarily an axial section, of thewormassemblyincluding a pinion for mating engagement with the castellated gear.

DESCRIPTlON OF THE PREFERRED EMBODIMENT The wrench, according to theinvention, has the well-known configuration and shape of a crescent-typewrench including a relatively flat main body'consisting of an elongatedhandle 10 and an enlarged head 11. The head 11 includes a base portion12.which'defines an outward facing base surface 13 for the jawopening-and includes an outward extending fixed jaw 14 defining a jawface perpendicular tothe base surface.

A movable jaw member 16 is slidably mounted on the head 11 forreciprocating movement in a direction parallel to the base surface ll3;and this member is generally L-shaped including a base portion 17 and anoutward extending movable jaw' 18, defining a jaw face perpendicular tothe base surface 13. and confronting the jaw face of the fixed jaw. Theelongated base portion 17 of the movable jaw member includes a spacedfrom the base surface 13. An elongated relatively narrow slot 24, in theplane of the wrench body, communicates the bore 23 with the base surface13. The bore 23 is provided to accommodate the cylindrical bead 20 ofthe movable jaw membenwith the rib 19 being accommodated in the slot 24and the movable jaw 18 defining shoulders confronting the base surface13 in assembled relation. in this manner, then, the movable jaw member16 is guided for'rectilinear movement' relative to the head 1 l.

A second larger cylindrical bore 25 is provided in the head base portion11, parallel to'and intersecting the smaller bore 23. The bore 25,however, does not extend completely through the head 11; but terminatesin a pilot recess 26 adjacent to the outer edge of the head.

A worm assembly 30, as best shown in FIG. 7, includes an elongated worm31 having an integraljournal shaft 32 extending from one end and isprovided with an axial base 33 extending into theworm body from theopposite end. The bore 33 accommodates a journal pin 34 and thecompression spring 35 which urges the journal pin outwardly relative tothe worm.

An axially elongated pinion 36, preferably having spline-type teeth, isnonrotatably fixed on the journal shaft 32 inwardly from its end.

in the tool assembly, the worm assembly 30 is received and confinedwithin the larger cylindrical bore 25 of the head 11, with the wormthreads in driving engagement with the teeth of the jaw member rack .20,and with the journal pin 34 is received .in the pilot recess 26 whichdefines a bearing for the journal pin.The worm assembly is retainedwithin the bore by meansof a bearing screw 38 threadedinto the inner endof the bore. The bearing screw is provided with an axial bore 39defining a rotary bearing for the journal shaft 32; and the inner faceofthe screw is engaged by the pinion 36, defining a thrust generallyrectangular in transverse cross section terminating at one end in an endwall 42 disposed intermediate the handle ends,.and opening at the otherend to the worm cavity 25. The opening into the worm cavity is a reducedcross section to define the shoulders 43 adjacent to the worm cavity andconfronting the end wall 42.

As best seen in FIGS. 2 and 4, the drive mechanism for the worm assemblyincludes a shaft 45 having a main body portion 46 provided with ahelical groove, and reduced diameter end portions defining front andrear journal shafts 47 and 48. The journal shafts accommodate therespective front and rear bearing blocks 50 and 51 which are preferablyfabricated of a suitable plastic-lubricating material, such as Nylon orTeflon, and which are dimensioned to be accommodated within the cavity41. The front bearing block 50 is received on the front journal shaft47, which extends through the bearing block; and a castellated gear 52,having forward facing teeth in square tooth form, is nonrotatablymounted on the end of the front journal shaft.

in assembly, the rear bearing block 51 is received within the cavity 41contiguous to the end wall 42, and the front bearing block 50 ispositioned contiguous to the shoulders 43, with the helical shaft body46 having a length slightly less than the distance between theconfronting faces of the bearing blocks and being axially confined bythe bearing blocks. The castellated gear 52 extends through the openingto the cavity 25 so that the teeth of the castellated gear engage theteeth of the splined gear 26 of the worm assembly in driving relation.

As best seen in FIGS. 1 and 4, rotation of the helical shaft 45 iseffected by means of a thumb button assembly 54 which is guided forrectilinear movement within a longitudinal slot 55 provided in a coverplate 56. The cavity 41 opens to a shallow recess 57 in the handle facesurrounding the cavity, the recess being dimensioned to receive andconfine the cover plate 56 in generally flush relation with the handleface. The handle and cover plate 56 may be provided with coacting meanssuch as a tongue and groove at the forward end of the wrench forretaining the cover plate, with the rearward end being retained by meansof a suitable screw, for example.

In assembled relation, as best seen in FIGS. 1 and 4, the cover plate 56retains and confines the bearing blocks 50 and 51 within the cavity 41,so that the axis of rotation of the shaft 46 is maintained in parallelrelation with the cover plate. The cover plate slot 55 is aligneddirectly over the shaft 45; and the thumb button assembly 54 includes aboss 58 at its inner end which is dimensioned to be received in slidingrelation within the helical groove of the shaft body 46.

OPERATION In operation, when the thumb button 54 is moved from therearward end of the tool toward the head 11, the shaft 45 andcastellated gear are rotated clockwise as viewed from the handle end ofthe wrench. This effects counterclockwise rotation of the worm assembly30 as viewed from the pinion end of this assembly, with accompanyingmovement of the jaw member 16 to close the movable jaw 18 toward thefixed jaw 14. Similarly, rearward movement of the thumb button assembly54 effects counterclockwise rotation of the shaft 45 and clockwiserotation of the worm 31 to move the movable jaw away from the fixed jaw.By way of example, movement of a thumb button 54 through a maximumexcursion of about 2 inches, effects almost instantaneous closure of thejaws from a maximal opening of /16 inch.

Because of the irreversibility of the worm-rack drive of the movablejaw, the jaws will remain in the desired wrenching position on a nut orbolt head when torque is applied.

While the preferred embodiment of the invention has been illustrated anddescribed, it will be understood by those skilled in the art thatchanges and modifications may be resorted to without departing from thespirit and scope of the invention.

What is claimed is:

1. In an adjustable jaw wrench including an elongated handle and anintegral head having a projecting fixed jaw; a member mounted forrectilinear movement on said head having a projecting jaw movable towardand away from the fixed jawa worm rotatabl sup orted in said headcoacting with said movable mem er or reciprocating said movable member;a shaft having a helical groove rotatably supported in said handle; anddrive means drivingly connecting said shaft and said worm; theimprovement comprising:

said drive means comprising a castellated gear nonrotatably fixed to theforward end of said shaft; and a pinion nonrotatably fixed to one end ofsaid worm and having teeth coacting with the teeth of said castellatedgear.

2. A wrench as set forth in claim 1 wherein the teeth of saidcastellated gear are rectangular in cross section; and wherein the teethof said pinion are elongated in an axial direction for mating engagementwith the teeth of the castellated gear.

3. A wrench as set forth in claim 1 wherein the axis of rotation of saidworm and pinion are at an angle inclined relative to the axis ofrotation of said shaft and castellated gear.

4. A wrench as set forth in claim 1 wherein said shaft comprises acentral body portion and end journal portions; bearing blocks forrotatably supporting the journal portions of helical shaft;

said handle being provided with elongated cavity for accommodating saidshaft and said bearing blocks; said cavity defining confronting endwalls for locating said bearing blocks in spaced relation, and saidshaft body defining shoulders for axially confining said shaft relativeto said bearing blocks;

a cover plate for retaining said bearing blocks within said cavity; andan actuator mounted for rectilinear sliding movement on said coverplate; said actuator including a boss engaging the helical groove ofsaid shaft to effect rotation thereof.

5. A wrench as set forth in claim 4 wherein said head is provided with abore transverse to said elongated cavity for accommodating said worm andpinion; said cavity including an opening of reduced sectioncommunicating with said bore for accommodating said castellated gear;and said cavity opening providing shoulders defining said confrontingend wall at the forward end of said cavity for locating one bearingblock.

6. A wrench as set forth in claim 4 wherein said bearing blocks arefabricated of a self-lubricating material.

7. A wrench as set forth in claim 4 wherein said shaft central bodyportion is of enlarged diameter and bears said helical groove, andwherein said end journal portions are of reduced diameter; said enlargeddiameter body portion defining said shoulders for axially confining theshaft relative to said bearing blocks.

8. A wrench as set forth in claim 5 wherein said worm bore communicatesadjacent one end thereof with said cavity and includes a reduceddiameter pilot recess at its other end; said worm having an axial recessextending into one end;

a journal pin dimensioned to be received in sliding relation within saidpilot recess and said worm recess; an a compression spring disposed inone of said recesses for urging said worm away from the pilot recess endof said worm bore;

and a thrust nut secured in said one end of said worm bore for resistingaxial movement of said worm.

9. A wrench as set forth in claim 8 wherein said worm includes a fixedjournal pin and thrust shoulder at its end opposite from the axialrecess; and wherein said thrust nut includes an axial bore defining abearing for said fixed journal pin.

10. A wrench as set forth in claim 9 wherein said pinion is nonrotatablymounted on said fixed journal pin, and defines a thrust shoulder for thewormpinion assembly.

1. In an adjustable jaw wrench including an elongated handle and anintegral head having a projecting fixed jaw; a member mounted forrectilinear movement on said head having a projecting jaw movable towardand away from the fixed jaw; a worm rotatably supported in said headcoacting with said movable member for reciprocating said movable member;a shaft having a helical groove rotatably supported in said handle; anddrive means drivingly connecting said shaft and said worm; theimprovement comprising: said drive means comprising a castellated gearnonrotatably fixed to the forward end of said shaft; and a pinionnonrotatably fixed to one end of said worm and having teeth coactingwith the teeth of said castellated gear.
 2. A wrench as set forth inclaim 1 wherein the teeth of said castellated gear are rectangular incross section; and wherein the teeth of said pinion are elongated in anaxial direction for mating engagement with the teeth of the castellatedgear.
 3. A wrench as set forth in claim 1 wherein the axis of rotationof said worm and pinion are at an angle inclined relative to the axis ofrotation of said shaft and castellated gear.
 4. A wrench as set forth inclaim 1 wherein said shaft comprises a central body portion and endjournal portions; bearing blocks for rotatably supporting the journalportions of helical shaft; said handle being provided with elongatedcavity for accommodating said shaft and said bearing blocks; said cavitydefining confronting end walls for locating said bearing blocks inspaced relation, and said shaft body defining shoulders for axiallyconfining said shaft relative to said bearing blocks; a cover plate forretaining said bearing blocks within said cavity; and an actuatormounted for rectilinear sliding movement on said cover plate; saidactuator including a boss engaging the helical groove of said shaft toeffect rotation thereof.
 5. A wrench as set forth in claim 4 whereinsaid head is provided with a bore transverse to said elongated cavityfor accommodating said worm and pinion; said cavity including an openingof reduced section communicating with said bore for accommodating saidcastellated gear; and said cavity opening providing shoulders definingsaid confronting end wall at the forward end of said cavity for locatingone bearing block.
 6. A wrench as set forth in claim 4 wherein saidbearing blocks are fabricated of a self-lubricating material.
 7. Awrench as set forth in claim 4 wherein said shaft central body portionis of enlarged diameter and bears said helical groove, and wherein saidend journal portions are of reduced diameter; said enlarged diameterbody portion defining said shoulders for axially confining the shaftrelative to said bearing blocks.
 8. A wrench as set forth in claim 5wherein said worm bore communicates adjacent one end thereof with saidcavity and includes a reduced diameter pilot recess at its other end;said worm having an axial recess extending into one end; a journal pindimensioned to be received in sliding relation within said pilot recessand said worm recess; a compression spring disposed in one of saidrecesses for urging said worm away from the pilot recess end of saidworm bore; and a thrust nut secured in said one end of said worm borefor resisting axial movement of said worm.
 9. A wrench as set forth inclaim 8 wherein said worm includes a fixed journal pin and thrustshoulder at its end opposite from the axial recess; and wherein saidthrust nut includes an axial bore defining a bearing for said fixedjournal pin.
 10. A wrench as set forth in claim 9 wherein said pinion isnonrotatably mounted on said fixed journal pin, and defines a thrustshoulder for the worm-pinion assembly.